From: "Masami Hiramatsu (Google)" <mhiramat@kernel.org>
To: Alexei Starovoitov <alexei.starovoitov@gmail.com>,
Steven Rostedt <rostedt@goodmis.org>,
Florent Revest <revest@chromium.org>
Cc: linux-trace-kernel@vger.kernel.org,
LKML <linux-kernel@vger.kernel.org>,
Martin KaFai Lau <martin.lau@linux.dev>,
bpf <bpf@vger.kernel.org>, Sven Schnelle <svens@linux.ibm.com>,
Alexei Starovoitov <ast@kernel.org>, Jiri Olsa <jolsa@kernel.org>,
Arnaldo Carvalho de Melo <acme@kernel.org>,
Daniel Borkmann <daniel@iogearbox.net>,
Alan Maguire <alan.maguire@oracle.com>,
Mark Rutland <mark.rutland@arm.com>,
Peter Zijlstra <peterz@infradead.org>,
Thomas Gleixner <tglx@linutronix.de>, Guo Ren <guoren@kernel.org>
Subject: [PATCH v9 08/36] function_graph: Remove logic around ftrace_graph_entry and return
Date: Mon, 15 Apr 2024 21:50:32 +0900 [thread overview]
Message-ID: <171318543205.254850.1420437462860854437.stgit@devnote2> (raw)
In-Reply-To: <171318533841.254850.15841395205784342850.stgit@devnote2>
From: Steven Rostedt (VMware) <rostedt@goodmis.org>
The function pointers ftrace_graph_entry and ftrace_graph_return are no
longer called via the function_graph tracer. Instead, an array structure is
now used that will allow for multiple users of the function_graph
infrastructure. The variables are still used by the architecture code for
non dynamic ftrace configs, where a test is made against them to see if
they point to the default stub function or not. This is how the static
function tracing knows to call into the function graph tracer
infrastructure or not.
Two new stub functions are made. entry_run() and return_run(). The
ftrace_graph_entry and ftrace_graph_return are set to them respectively
when the function graph tracer is enabled, and this will trigger the
architecture specific function graph code to be executed.
This also requires checking the global_ops hash for all calls into the
function_graph tracer.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
---
Changes in v2:
- Fix typo and make lines shorter than 76 chars in the description.
- Remove unneeded return from return_run() function.
---
kernel/trace/fgraph.c | 67 +++++++++-------------------------------
kernel/trace/ftrace.c | 2 -
kernel/trace/ftrace_internal.h | 2 -
3 files changed, 15 insertions(+), 56 deletions(-)
diff --git a/kernel/trace/fgraph.c b/kernel/trace/fgraph.c
index b9a2399b75ee..6f3ba8e113c1 100644
--- a/kernel/trace/fgraph.c
+++ b/kernel/trace/fgraph.c
@@ -145,6 +145,17 @@ add_fgraph_index_bitmap(struct task_struct *t, int offset, unsigned long bitmap)
t->ret_stack[offset] |= (bitmap << FGRAPH_INDEX_SHIFT);
}
+/* ftrace_graph_entry set to this to tell some archs to run function graph */
+static int entry_run(struct ftrace_graph_ent *trace)
+{
+ return 0;
+}
+
+/* ftrace_graph_return set to this to tell some archs to run function graph */
+static void return_run(struct ftrace_graph_ret *trace)
+{
+}
+
/*
* @offset: The index into @t->ret_stack to find the ret_stack entry
* @index: Where to place the index into @t->ret_stack of that entry
@@ -675,7 +686,6 @@ extern void ftrace_stub_graph(struct ftrace_graph_ret *);
/* The callbacks that hook a function */
trace_func_graph_ret_t ftrace_graph_return = ftrace_stub_graph;
trace_func_graph_ent_t ftrace_graph_entry = ftrace_graph_entry_stub;
-static trace_func_graph_ent_t __ftrace_graph_entry = ftrace_graph_entry_stub;
/* Try to assign a return stack array on FTRACE_RETSTACK_ALLOC_SIZE tasks. */
static int alloc_retstack_tasklist(unsigned long **ret_stack_list)
@@ -758,46 +768,6 @@ ftrace_graph_probe_sched_switch(void *ignore, bool preempt,
}
}
-static int ftrace_graph_entry_test(struct ftrace_graph_ent *trace)
-{
- if (!ftrace_ops_test(&global_ops, trace->func, NULL))
- return 0;
- return __ftrace_graph_entry(trace);
-}
-
-/*
- * The function graph tracer should only trace the functions defined
- * by set_ftrace_filter and set_ftrace_notrace. If another function
- * tracer ops is registered, the graph tracer requires testing the
- * function against the global ops, and not just trace any function
- * that any ftrace_ops registered.
- */
-void update_function_graph_func(void)
-{
- struct ftrace_ops *op;
- bool do_test = false;
-
- /*
- * The graph and global ops share the same set of functions
- * to test. If any other ops is on the list, then
- * the graph tracing needs to test if its the function
- * it should call.
- */
- do_for_each_ftrace_op(op, ftrace_ops_list) {
- if (op != &global_ops && op != &graph_ops &&
- op != &ftrace_list_end) {
- do_test = true;
- /* in double loop, break out with goto */
- goto out;
- }
- } while_for_each_ftrace_op(op);
- out:
- if (do_test)
- ftrace_graph_entry = ftrace_graph_entry_test;
- else
- ftrace_graph_entry = __ftrace_graph_entry;
-}
-
static DEFINE_PER_CPU(unsigned long *, idle_ret_stack);
static void
@@ -939,18 +909,12 @@ int register_ftrace_graph(struct fgraph_ops *gops)
ftrace_graph_active--;
goto out;
}
-
- ftrace_graph_return = gops->retfunc;
-
/*
- * Update the indirect function to the entryfunc, and the
- * function that gets called to the entry_test first. Then
- * call the update fgraph entry function to determine if
- * the entryfunc should be called directly or not.
+ * Some archs just test to see if these are not
+ * the default function
*/
- __ftrace_graph_entry = gops->entryfunc;
- ftrace_graph_entry = ftrace_graph_entry_test;
- update_function_graph_func();
+ ftrace_graph_return = return_run;
+ ftrace_graph_entry = entry_run;
ret = ftrace_startup(&graph_ops, FTRACE_START_FUNC_RET);
}
@@ -986,7 +950,6 @@ void unregister_ftrace_graph(struct fgraph_ops *gops)
if (!ftrace_graph_active) {
ftrace_graph_return = ftrace_stub_graph;
ftrace_graph_entry = ftrace_graph_entry_stub;
- __ftrace_graph_entry = ftrace_graph_entry_stub;
ftrace_shutdown(&graph_ops, FTRACE_STOP_FUNC_RET);
unregister_pm_notifier(&ftrace_suspend_notifier);
unregister_trace_sched_switch(ftrace_graph_probe_sched_switch, NULL);
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index da1710499698..fef833f63647 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -235,8 +235,6 @@ static void update_ftrace_function(void)
func = ftrace_ops_list_func;
}
- update_function_graph_func();
-
/* If there's no change, then do nothing more here */
if (ftrace_trace_function == func)
return;
diff --git a/kernel/trace/ftrace_internal.h b/kernel/trace/ftrace_internal.h
index 5012c04f92c0..19eddcb91584 100644
--- a/kernel/trace/ftrace_internal.h
+++ b/kernel/trace/ftrace_internal.h
@@ -42,10 +42,8 @@ ftrace_ops_test(struct ftrace_ops *ops, unsigned long ip, void *regs)
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
extern int ftrace_graph_active;
-void update_function_graph_func(void);
#else /* !CONFIG_FUNCTION_GRAPH_TRACER */
# define ftrace_graph_active 0
-static inline void update_function_graph_func(void) { }
#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
#else /* !CONFIG_FUNCTION_TRACER */
next prev parent reply other threads:[~2024-04-15 12:50 UTC|newest]
Thread overview: 59+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-04-15 12:48 [PATCH v9 00/36] tracing: fprobe: function_graph: Multi-function graph and fprobe on fgraph Masami Hiramatsu (Google)
2024-04-15 12:49 ` [PATCH v9 01/36] tracing: Add a comment about ftrace_regs definition Masami Hiramatsu (Google)
2024-04-24 12:23 ` Florent Revest
2024-04-24 13:19 ` Florent Revest
2024-04-24 14:31 ` Masami Hiramatsu
2024-04-15 12:49 ` [PATCH v9 02/36] tracing: Rename ftrace_regs_return_value to ftrace_regs_get_return_value Masami Hiramatsu (Google)
2024-04-15 12:49 ` [PATCH v9 03/36] x86: tracing: Add ftrace_regs definition in the header Masami Hiramatsu (Google)
2024-04-15 12:49 ` [PATCH v9 04/36] function_graph: Convert ret_stack to a series of longs Masami Hiramatsu (Google)
2024-04-15 12:49 ` [PATCH v9 05/36] fgraph: Use BUILD_BUG_ON() to make sure we have structures divisible by long Masami Hiramatsu (Google)
2024-04-15 12:50 ` [PATCH v9 06/36] function_graph: Add an array structure that will allow multiple callbacks Masami Hiramatsu (Google)
2024-04-15 12:50 ` [PATCH v9 07/36] function_graph: Allow multiple users to attach to function graph Masami Hiramatsu (Google)
2024-04-20 3:52 ` Steven Rostedt
2024-04-20 8:56 ` Masami Hiramatsu
2024-04-15 12:50 ` Masami Hiramatsu (Google) [this message]
2024-04-15 12:50 ` [PATCH v9 09/36] ftrace/function_graph: Pass fgraph_ops to function graph callbacks Masami Hiramatsu (Google)
2024-04-15 12:50 ` [PATCH v9 10/36] ftrace: Allow function_graph tracer to be enabled in instances Masami Hiramatsu (Google)
2024-04-15 12:51 ` [PATCH v9 11/36] ftrace: Allow ftrace startup flags exist without dynamic ftrace Masami Hiramatsu (Google)
2024-04-15 12:51 ` [PATCH v9 12/36] function_graph: Have the instances use their own ftrace_ops for filtering Masami Hiramatsu (Google)
2024-04-15 12:51 ` [PATCH v9 13/36] function_graph: Use a simple LRU for fgraph_array index number Masami Hiramatsu (Google)
2024-04-15 12:51 ` [PATCH v9 14/36] function_graph: Add "task variables" per task for fgraph_ops Masami Hiramatsu (Google)
2024-04-15 12:51 ` [PATCH v9 15/36] function_graph: Move set_graph_function tests to shadow stack global var Masami Hiramatsu (Google)
2024-04-15 12:52 ` [PATCH v9 16/36] function_graph: Move graph depth stored data " Masami Hiramatsu (Google)
2024-04-15 12:52 ` [PATCH v9 17/36] function_graph: Move graph notrace bit " Masami Hiramatsu (Google)
2024-04-15 12:52 ` [PATCH v9 18/36] function_graph: Implement fgraph_reserve_data() and fgraph_retrieve_data() Masami Hiramatsu (Google)
2024-04-15 12:52 ` [PATCH v9 19/36] function_graph: Add selftest for passing local variables Masami Hiramatsu (Google)
2024-04-15 12:52 ` [PATCH v9 20/36] ftrace: Add multiple fgraph storage selftest Masami Hiramatsu (Google)
2024-04-15 12:53 ` [PATCH v9 21/36] function_graph: Pass ftrace_regs to entryfunc Masami Hiramatsu (Google)
2024-04-15 12:53 ` [PATCH v9 22/36] function_graph: Replace fgraph_ret_regs with ftrace_regs Masami Hiramatsu (Google)
2024-04-15 12:53 ` [PATCH v9 23/36] function_graph: Pass ftrace_regs to retfunc Masami Hiramatsu (Google)
2024-04-15 12:53 ` [PATCH v9 24/36] fprobe: Use ftrace_regs in fprobe entry handler Masami Hiramatsu (Google)
2024-04-15 12:53 ` [PATCH v9 25/36] fprobe: Use ftrace_regs in fprobe exit handler Masami Hiramatsu (Google)
2024-04-15 12:54 ` [PATCH v9 26/36] tracing: Add ftrace_partial_regs() for converting ftrace_regs to pt_regs Masami Hiramatsu (Google)
2024-04-15 12:54 ` [PATCH v9 27/36] tracing: Add ftrace_fill_perf_regs() for perf event Masami Hiramatsu (Google)
2024-04-15 12:54 ` [PATCH v9 28/36] tracing/fprobe: Enable fprobe events with CONFIG_DYNAMIC_FTRACE_WITH_ARGS Masami Hiramatsu (Google)
2024-04-15 12:54 ` [PATCH v9 29/36] bpf: Enable kprobe_multi feature if CONFIG_FPROBE is enabled Masami Hiramatsu (Google)
2024-04-25 20:09 ` Andrii Nakryiko
2024-04-29 14:57 ` Masami Hiramatsu
2024-04-15 12:54 ` [PATCH v9 30/36] ftrace: Add CONFIG_HAVE_FTRACE_GRAPH_FUNC Masami Hiramatsu (Google)
2024-04-15 12:55 ` [PATCH v9 31/36] fprobe: Rewrite fprobe on function-graph tracer Masami Hiramatsu (Google)
2024-04-15 12:55 ` [PATCH v9 32/36] tracing/fprobe: Remove nr_maxactive from fprobe Masami Hiramatsu (Google)
2024-04-15 12:55 ` [PATCH v9 33/36] selftests: ftrace: Remove obsolate maxactive syntax check Masami Hiramatsu (Google)
2024-04-15 12:55 ` [PATCH v9 34/36] selftests/ftrace: Add a test case for repeating register/unregister fprobe Masami Hiramatsu (Google)
2024-04-15 12:55 ` [PATCH v9 35/36] Documentation: probes: Update fprobe on function-graph tracer Masami Hiramatsu (Google)
2024-04-15 12:55 ` [PATCH v9 36/36] fgraph: Skip recording calltime/rettime if it is not nneeded Masami Hiramatsu (Google)
2024-04-25 20:15 ` Andrii Nakryiko
2024-04-29 14:56 ` Masami Hiramatsu
2024-04-19 5:36 ` [PATCH v9 00/36] tracing: fprobe: function_graph: Multi-function graph and fprobe on fgraph Masami Hiramatsu
2024-04-19 8:01 ` Steven Rostedt
2024-04-24 13:35 ` Florent Revest
2024-04-25 15:10 ` Masami Hiramatsu
2024-04-25 20:31 ` Andrii Nakryiko
2024-04-28 23:25 ` Steven Rostedt
2024-04-29 20:28 ` Andrii Nakryiko
2024-04-29 13:51 ` Masami Hiramatsu
2024-04-29 20:25 ` Andrii Nakryiko
2024-04-30 13:32 ` Masami Hiramatsu
2024-04-30 16:29 ` Andrii Nakryiko
2024-05-02 2:06 ` Masami Hiramatsu
2024-05-07 21:04 ` Andrii Nakryiko
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